chrome/renderer/resources/extensions/tts_engine_custom_bindings.js

// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Custom binding for the ttsEngine API.

var binding = apiBridge || require('binding').Binding.create('ttsEngine');
var registerArgumentMassager = bindingUtil ?
    $Function.bind(bindingUtil.registerEventArgumentMassager, bindingUtil) :
    require('event_bindings').registerArgumentMassager;
var sendRequest = bindingUtil ?
    $Function.bind(bindingUtil.sendRequest, bindingUtil) :
    require('sendRequest').sendRequest;

registerArgumentMassager('ttsEngine.onSpeak', function(args, dispatch) {
  var text = args[0];
  var options = args[1];
  var requestId = args[2];
  var sendTtsEvent = function(event) {
    chrome.ttsEngine.sendTtsEvent(requestId, event);
  };
  dispatch([text, options, sendTtsEvent]);
});

binding.registerCustomHook(function(api) {
  // Provide a warning if deprecated parameters are used.
  api.apiFunctions.setHandleRequest('updateVoices', function(voices) {
    for (var i = 0; i < voices.length; i++) {
      if (voices[i].gender) {
        console.warn(
            'chrome.ttsEngine.updateVoices: ' +
            'Voice gender is deprecated and values will be ignored ' +
            'starting in Chrome 71.');
        break;
      }
    }
    sendRequest(
        'ttsEngine.updateVoices', [voices],
        bindingUtil ? undefined : this.definition.parameters, undefined);
  });
}.bind(this));

if (!apiBridge)
  exports.$set('binding', binding.generate());